Meths should do the trick but just be careful about adding too much to the water bottle. It may affect the window rubbers I'm told. I was always convinced the black stuff was just muck coming off
the cheapo baby wipes would do it, if they have alcohol in them, failing that glass/mirror wipes work quite well, or just plain old washing up-liquid and warm water.
White vinegar works good on both glass & wiper blades. It's alot cheaper too compared to all those 'flashy' cleaning products. When you given everything a good wipe over just a quick rinse & your away.
To be sure I would do all your windows.
Our dealer did the same to my car just before I collected it. It's the fault of the valeter who is probably some teenage kid from school working weekends who doesn't know any better & who hasn't been told not to wax the windows.